Method callback

third_party/subscriptions-project/swg.js:15440–15447

(event)

  static sendAndWaitForResponse(
      data, eventType, responseType, responseHandler) {
    function callback(event) {
      if (event.data[responseType]) {
        responseHandler(event);
        // We only want to process the response from the payframe once.
        // so stop listening to the event once processed.
        PayFrameHelper.removeMessageEventListener_(callback);
      }
    }

    PayFrameHelper.addMessageEventListener_(callback);